When making a garment it is always a good idea to measure it against a garment you already wear that you know is your size.
I used a hook 4 which is 0.5 sizes larger than I would usually use for DK to obtain a looser fabric.
Needed
Yarn
I used 6 Balls of Highland Heather in Grist (Use any colour you like!) Hook
I used both a 4 and a 3.5 for DK, the yarn states a 4.
Scissors
Stitch markers
Darning needle